The invention is in the field of user-manipulated toys. More particularly, the invention is an apparatus in the form of a yo-yo that functions in an improved manner relative to the prior art. This is achieved through the use of an active starburst tether engagement system located in one or both of the yo-yo""s side members. The system makes use of a starburst-shaped array of movable engagement ribs that face the tether and are located proximate the yo-yo""s axle structure. Each of said ribs is independently movable and is located at the end of a flexible finger that enables the rib to move in a direction substantially parallel to the yo-yo""s axis of rotation. In one embodiment, the flexible finger members, and their associated engagement ribs, are secured to a common support ring. In a second embodiment of the invention, the flexible fingers are integral with the associated side member whereby the side member and flexible fingers are in the form of a unitary part.
Most yo-yos are in the form of two disk-shaped side members that are rigidly connected to each other by some form of axle structure. The axle structure may be an assembly of multiple parts, or merely be in the form of a dowel or a riveted pin, and may be made of metal and/or wood and/or plastic. In many modern yo-yos, the axle structure includes a center-located bearing or other member that is secured to, and rotatable on, an elongated axle member.
The axle structure also forms an anchor for one end of a string-type tether. This is accomplished by having the tether""s end-located loop encircle a portion of the axle structure.
The free end of the tether is usually tied to create a loop. This loop is normally placed about one of a user""s fingers to thereby secure the yo-yo to the user. When the tether is wound about the axle structure and the yo-yo is released from the user""s hand, the yo-yo will begin to rapidly spin as it moves away from the user""s hand and the tether unwinds from the axle structure. Once the tether is fully unwound, the yo-yo may xe2x80x9csleepxe2x80x9d at the end of the tether, whereby the yo-yo continues to spin without the tether rewinding on the axle structure.
Once the yo-yo is sleeping, there are a number of tricks that a person can perform with the spinning yo-yo. In some of these tricks, the spinning yo-yo is temporarily placed upon a portion of the tether intermediate of the tether""s two ends. At the completion of most yo-yo tricks, the user will make a rapid tug/jerk on the tether. This will result in a brief tightening of the tether, which is then automatically followed by a temporary slackening of the tether. Once the tether goes slack, the tether""s twist will cause one or more portions of the tether to move and thereby contact a spinning portion of the yo-yo. Once contact has occurred, the tether portion can become snagged on a spinning portion of the yo-yo and this will cause the tether to wind about the axle structure. The winding of the tether on the axle structure causes the yo-yo to return to the user""s hand.
There are three crucial performance characteristics of a yo-yo that enable a user to perform yo-yo tricks. The yo-yo must be capable of sleeping for an extended period of time, it should return on command, and it should be smooth on the tether.
Concerning a yo-yo""s sleep time, the longer the yo-yo can be made to sleep, the more time the user will have to complete any particular yo-yo trick. It is well known that by minimizing friction in the yo-yo""s components, one can maximize the yo-yo""s sleep time. It is also known that whenever the tether even slightly rubs against a spinning portion of the yo-yo, the created friction will also reduce the yo-yo""s sleep time.
For a yo-yo to return on command, the structure and design of the yo-yo must be such that when the user causes the tether to briefly go slack, a portion of the tether can snag a spinning portion of the yo-yo. The ability of the tether to snag one of the yo-yo""s spinning side members is often enhanced through the use of particular adaptations in the tether-facing surface of said side members. A commonly employed adaptation of this type is the use of a starburst-shaped array of rigid, fixed ribs that extend toward the tether from each side member""s tether-facing surface. The tether-facing surface of a side member is herein defined as the surface of the side member that is normally oriented substantially perpendicular to the yo-yo""s axis of rotation and that faces a portion of the yo-yo""s tether at all times. While the ribs facilitate tether engagement, they also make it is easy for a user to inadvertently cause the tether to rub on the ribs during a yo-yo trick. This can result in an unplanned return of the yo-yo to the user""s hand, or less dramatically, increase tether wear and reduce sleep time.
Concerning a yo-yo""s ability to be smooth on the tether, this refers to a yo-yo""s ability to be temporarily placed on a middle portion of the tether without the tether inadvertently snagging a spinning portion of the yo-yo. If during a trick, the tether snags a spinning portion of the yo-yo at the wrong moment, the yo-yo will immediately return to the user""s hand and the trick will be ruined. The tendency of the tether to inadvertently snag on a spinning portion of the yo-yo is affected by the yo-yo""s string gap, the configuration of each side member""s tether-facing surface and the configuration of the yo-yo""s axle structure.
A yo-yo""s string gap is herein defined as the area between the yo-yo""s side members. The larger the width of the string gap proximate the axle structure, the further the tether has to travel to snag on either of the side members. However, too wide a gap may preclude a user""s ability to cause the tether to engage a spinning portion of the yo-yo, with the result that a user cannot make the yo-yo return to his or her hand.
One other consideration involved in the design/performance of yo-yos is the wear rate of the yo-yo""s tether and the components used to engage said tether. It is a common occurrence for a tether to wear out over time. This is due both to the physical strains put on the tether during use of the yo-yo, and to the wear that occurs whenever the tether contacts a spinning portion of the yo-yo. A tether will normally wear out long before significant wear occurs in the tether engagement structure. However, once significant wear occurs in the yo-yo""s tether engagement structure, the yo-yo""s performance will degrade and the yo-yo will eventually become unusable.
The invention is an improved yo-yo in which a unique tether engagement structure is employed to facilitate and control tether engagement. The yo-yo features at least one side member that employs an active starburst tether engagement system. The system features a starburst-shaped array of movable engagement ribs that are flexibly secured to the associated side member. This is unlike prior art yo-yos that employ a fixed set of raised ribs located in a starburst-shaped array. It should be noted that the term xe2x80x9cstarburst-shapedxe2x80x9d is herein defined as a plurality of ray-like members that are spaced about, and extend away from, a center point.
Most of the time, the movable engagement ribs protrude outwardly from a substantially planar, tether-facing surface of the associated side member. The ribs are located proximate, and preferably adjacent to, the yo-yo""s axle structure. In the preferred embodiment, each of the ribs has a triangular shape, with linear edges.
In some situations, the movable engagement ribs are moved by the tether in a direction that is substantially parallel to the yo-yo""s axis of rotation and is also substantially perpendicular to the side member""s tether-facing surface. This is enabled through the use of flexible finger members that are secured to, and preferably extensions of, the ribs. Each flexible finger member has an elongated shape with a relatively narrow cross-section. These characteristics, in combination with the material used to make the finger members, gives each finger member a degree/amount of flexibility. In the preferred embodiment, the finger members are made of a flexible plastic material. Other materials may alternatively be employed, with material choice being made in combination with any flexibility that is derived through the shape of the fingers to preferably enable the finger members to act as springs and to exhibit considerable bending moment. It should be noted that changes made in the material or shape of the finger members could affect the yo-yo""s performance.
In a first embodiment of the invention, all of a side member""s flexible finger members are attached to a common support ring. The ring is preferably releasably secured to a back portion of the associated side member. To enable the engagement ribs to protrude into the string gap, the side member""s tether-facing surface includes a plurality of shaped apertures through which the ribs pass. The finger members thereby spring-bias the ribs toward the tether.
In a second embodiment of the invention, all of a side member""s flexible finger members and attached engagement ribs, as well as the side member itself, are in the form of a unitary part. This requires the side member to be made of a material, such as plastic, that will enable the flexible fingers to flex and thereby spring-bias the engagement ribs toward the tether.
The operation of the active starburst tether engagement system is most noticeable during the performance of yo-yo tricks. When the yo-yo is sleeping at the end of the tether, the tether""s end loop will normally be centered on the axle structure and the tether will preferably be spaced from the engagement ribs of both side members. At this point, there is no impetus for the yo-yo to return to the user""s hand since there is no contact between the tether and the ends of the engagement ribs.
During the performance of most yo-yo tricks, the yo-yo will be manipulated through movement of the tether. Until the very end of the trick, a user must take care not to have the tether contact a spinning portion of the yo-yo, lest the yo-yo should be caused to inadvertently return or be slowed to the extent that it cannot return at the end of the trick. While the invention does not prevent inadvertent tether contact with a side member, it ameliorates the problem.
In the invention, the active starburst tether engagement system allows for some movement of the engagement ribs. When the tether is in a taut condition and a user inadvertently causes the tether to contact one or more of the ribs, the resultant slight pressure on the rib(s) causes the rib(s) to move away from the tether. In this manner, a glancing contact will not cause an immediate return of the yo-yo. While such a glancing contact will cause some slowing of the yo-yo, the ability of the ribs to move away from the tether will minimize the braking action of the contact. It should be noted that by allowing the ribs to move away from the tether, any inadvertent contact will produce much less wear in both the tether and the ribs than would be caused if the ribs were not movable.
When the user is ready to have a yo-yo in accordance with the invention return to his or her hand, the user causes the tether to go slack in the same manner that is used with prior art yo-yos. Once the tether is slack, it will tend to move toward one or both of the yo-yo""s side members. Since the slack tether cannot exert any significant pressure on the movable engagement ribs, the ribs will not move away from the tether and they will snag the tether and cause the yo-yo to return to the user""s hand.
Since the tether will only tend to lockably snag one of the yo-yo""s movable ribs when the tether has been purposefully slackened by the user, it is possible for the ribs to protrude further into the string gap than is usually found in prior art yo-yos having fixed ribs. Having the ribs protrude further into the string gap makes it easier for a user to cause the yo-yo to return and also provides the yo-yo with a faster response time.
The invention enables a yo-yo to perform in an extremely responsive manner while at the same time minimizing the adverse affects that would follow an inadvertent contact between the tether and one of the yo-yo""s side members. In this manner, a yo-yo in accordance with the invention will be able to sleep longer and be smoother on the string than prior art yo-yos. Concerning the ability of the yo-yo to return on command, the yo-yo""s design can enable the ribs to protrude further into the string gap and thereby make it easier to cause the yo-yo to return while providing the yo-yo with a quicker response time.